The present invention relates generally to a semiconductor memory device, and more particularly to an anti-fuse repair control circuit, in which a semiconductor memory device integrated into a multi-chip package is improved to individually perform an anti-fuse repair, and a semiconductor device including a DRAM which has the anti-fuse repair control circuit when integrated into a multi-chip package.
Recently, a variety of mobile devices have been developed and a semiconductor device having multi-functions is required in order to improve the function of those mobile devices.
The semiconductor device as a single memory chip is limited in realizing the required multi-functions. Accordingly, a semiconductor device is often realized in a structure of a multi-chip package, in which the semiconductor device is integrated with the same DRAMs in the same package or is integrated with a DRAM and a flash memory in the same package.
For a semiconductor device, which is realized as a package as described above, an anti-fuse repair technique is used to repair a bit fail occurring in an integrated chip, such as a DRAM.
According to the anti-fuse repair technique, a bit fail is repaired by melting an anti-fuse with a high voltage between both ends of the anti-fuse corresponding to a position where a bit fail has occurred, not by cutting a fuse element with a laser beam.
A typical multi-chip package has a structure in which an input address, a clock signal, and a command are shared by the mounted chips. FIG. 1A illustrates a case in which a flash memory and two mobile DRAMs are integrated into one package. FIG. 1B illustrates a case in which two mobile DRAMs are integrated into one package.
As illustrated in FIGS. 1A and 1B, two DRAMS included in a multi-chip package have separate data input/output (DATA 10) ports but share an input address, a clock signal, and a command.
Therefore, if a bit fail occurs in either one of the DRAMs, then repair information is transmitted to both DRAMs. As a result, the DRAM in which the bit fail occurred as well as the normal DRAM, in which no bit fail occurred, perform an anti-fuse repair operation at the same time.
Accordingly, in performing an anti-fuse repair operation in a conventional multi-chip package by a semiconductor device, a normal DRAM would perform an unnecessary anti-fuse repair operation, because the DRAMs in a conventional multi-chip package share the input address and the clock signal and the command as discussed above. Consequently, in a conventional multi-chip package, the overall repair efficiency of the semiconductor device decreases to less than half due to performance of the unnecessary anti-fuse repair operations.